Table 3.

Indirect effects of sleep, physical activity, and diet on the association between shift work and ILI/ARI incidence rate (complete case analysis, N=396) ^a [ARI=acute respiratory illness; CI=confidence interval; ILI=influenza-like illness; IRR=incidence rate ratio].

	Indirect effects b
	IRR	95% CI
Short sleep duration	1.05	0.89–1.31
Long sleep duration	0.99	0.91–1.06
Poor sleep quality	1.29 c	1.02–1.95
Physical activity during leisure	1.00	0.95–1.06
Physical activity at work	1.07	0.92–1.28
Number of meals	1.01	0.91–1.13
Number of snacks	1.04	0.97–1.16

^a Adjusted for age, gender, occupation, influenza vaccination status, and general perceived health.

^b Indirect effects are calculated by taking e (base of the natural logarithm) raised to the power of the product of the a-paths and b-paths (eg, e(a1×b1)=e(1.042×0.048)=1.05).

^c P<0.05.